1. Field of the Invention
This invention relates to a method for making a screen, more particularly to a method for making a screen for filtering pulp during the manufacturing of paper.
2. Description of the Related Art
In paper manufacturing, pulp is sifted through a series of pulp screens of screening machines in order to sort pulp according to size. Referring to FIGS. 1 and 2, a conventional pulp screen 1 has a plurality of spaced annular supporting members 21 and a plurality of parallel elongated strips 3 attached to the annular supporting members 21 to form slots 31 therebetween. Referring again to FIG. 2, in order to make the conventional pulp screen 1, elongated supporting plates 2 are disposed spacedly from one another. Elongated strips 3 are juxtaposed parallel to one another and are welded transversely to the elongated supporting plates 2 to form a screen plate with a plurality of slots 31. The screen plate is then rolled to form the pulp screen 1 with a cylindrical shape. A main drawback in this method for making the conventional pulp screen 1 is that the welded portions of the elongated supporting plates 2 and the elongated strips 3 are prone to deformation as a result of bending stress present during the rolling process. Furthermore, the welding process is time-consuming and is not convenient, thereby lowering the efficiency and increasing the manufacturing cost.